155640020 has 24 divisors (see below), whose sum is σ = 344047200. Its totient is φ = 58979232.

The previous prime is 155640007. The next prime is 155640029. The reversal of 155640020 is 20046551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155640029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 204410 + ... + 205169.

It is an arithmetic number, because the mean of its divisors is an integer number (14335300).

Almost surely, 2^155640020 is an apocalyptic number.

155640020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

155640020 is an abundant number, since it is smaller than the sum of its proper divisors (188407180).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

155640020 is a wasteful number, since it uses less digits than its factorization.

155640020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409607 (or 409605 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 155640020 is about 12475.5769405667. The cubic root of 155640020 is about 537.9068720292.

Adding to 155640020 its reverse (20046551), we get a palindrome (175686571).

The spelling of 155640020 in words is "one hundred fifty-five million, six hundred forty thousand, twenty".